| 摘要 |
PROBLEM TO BE SOLVED: To produce an Si3 N4 sintered compact usable at a high temp. of >=1,250 deg.C and having high high-temp. strength. SOLUTION: When a powdery mixture of Si3 N4 powder as a principal component with a 1st and a 2nd sintering aids is compacted and sintered to obtain an Si3 N4 sintered compact, the average particle diameter of the Si3 N4 powder is regulated to 0.1-1.0μm, powder of oxide of one or more kinds of the group IIIa elements is used as the 1st sintering aid and powder of oxide of one or more kinds of elements selected from among Zr, Hf, Nb, Ta and W is used as the 2nd sintering aid. The average particle diameter of the 1st sintering aid is regulated to 0.1-10 times that of the Si3 N4 powder. In the 2nd sintering aid, the total number of particles whose average particle diameter is 10-100 times that of the Si3 N4 powder is allowed to account for 5-50% and the 2nd sintering aid is added by <=10wt.%. |
